First Identify the Price You Are Looking At
The name fair price is used for different measures. In cross-exchange analysis it may mean a reference across quotes; in a futures specification it may refer to an exchange-calculated price. Do not assume these values are identical.
Bid / ask and mid
Bid is a resting buy price; ask is a resting sell price. Mid is halfway between the best bid and ask. There may be no executable order at that midpoint.
Median across available markets
The central value in a sorted price sample. It helps identify an unusual venue, but depends on coverage, units and the kinds of quotes in the sample.
Index price / mark price
An index price follows an exchange’s methodology for underlying-asset price sources. Mark price serves the futures contract’s pricing and risk mechanics; Bybit, for example, uses it for liquidations and unrealized P&L. It can differ from the last trade.
Exchange methodology: Bybit — Index Price · Bybit — Mark Price.
Use a Deviation to Investigate Its Cause
When a percentage is large, start with explanations you can check. Quotes may differ because of a wide order book, transfer restrictions, contract terms or mismatched timestamps. A ticker compared without checking the asset and contract multiplier can also create a false comparison.
Is there executable size?
Inspect bids, asks and depth rather than only a last trade or average price.
Can you use the route?
For a transfer, verify the specific network and deposit/withdrawal status. For a hedge, verify both contracts and margin availability.
Are you comparing the same thing?
Match the underlying, quote currency, market type and contract multiplier. Spot and perpetual markets can have their own price basis.
A deviation percentage cannot establish that an exchange is manipulating a market. It identifies a numerical difference. Determining the cause requires additional evidence.
What “vs med” Means in VoltArb
Scanner’s All prices panel displays quotes for available markets. With both sides present, it uses the midpoint of best bid and ask; with only one side available, it uses that side. The reference is the sample’s unweighted median: with an even number of values, the average of the two central values.
Positive means above this reference; negative means below it. Both signs describe a comparison, not an instruction to buy or sell. The sample is limited to available data, not every trade or exchange worldwide. A one-sided quote adds uncertainty.
Other panels can display Fair Px, Market median and Δ Med from market data. Their quote sample can differ from the All prices panel. Read the metric label first; an exchange Fair Px should not be replaced with a local midpoint or assumed identical to the panel median.
How to Investigate a Quote in Scanner
- Open Scanner and find an asset. Verify quote currency and market types.
- Select a route and expand All prices. Identify the unusual venue and inspect the bids/asks behind its deviation.
- Compare the buy ask and sell bid. Check depth for the intended quantity, then verify the transfer route or both futures contracts.
- If another venue has an available route, open it and repeat the check. Switching rows does not execute a trade.
Two Worked Examples
All values below are invented for explanation. They do not describe a specific token, exchange or executed trade.
1. One Venue Sits Above the Reference
Five available midpoints are $0.990, $0.998, $1.000, $1.002 and $1.080. The median is $1.000. The last venue is +8% above it. With a bid of $1.079 and ask of $1.081, both sides of its quote reflect the difference.
Next you need resting order size, costs and route availability. The median does not imply that this venue must fall: the others could rise, all prices could move, or the gap could persist.
2. The Same +8%, Without a Higher Executable Sell Price
Now give that venue a bid of $0.980 and an ask of $1.180. Its midpoint is still $1.080, or +8% against the $1.000 median. But the best resting buyer is below the median: you cannot sell a market order at $1.080.
The error is substituting an attractive average for the executable side of the book. Deviation helps choose what to investigate; a profit estimate requires available execution.
Turn the Observation Into a Testable Hypothesis
A useful note is: “Venue A quotes above the others; I will check whether the required quantity can be sold and how the other leg is covered.” Add the timestamp, market type, bids/asks, size and any restriction found. “The token is 8% overpriced” loses most of that information.
For a spot route, include transfers and rebalancing. For a futures pair, include the price gap at exit, funding and separate margin accounts. Reducing directional exposure does not mean one venue’s loss is automatically covered by the other venue’s balance.
Which Metric Answers Your Question?
| Metric | What It Helps Check |
|---|---|
| vs med | Whether a quote differs from the available sample. Does not determine a future fill price. |
| Route spread | How selected buy and sell sides compare. Size, costs and timing require separate checks. |
| Mark price | The calculated price used by a futures contract’s rules. Does not replace bid/ask for execution estimates. |
Common Questions
Is a larger deviation a stronger signal?
It is a more noticeable difference to investigate. Without current bids/asks, depth and an available route, its trading relevance is unknown.
Does a below-median price mean the asset is undervalued?
It only means a lower price within the current quote sample. The median is not a valuation of a business, tokenomics or future asset value.
Where should I start in VoltArb?
Open Scanner, select a route and compare available venues in All prices. Then inspect the books on both legs.
Metric methodology and copy reviewed on October 18, 2026. Exchange price definitions use the official Bybit sources linked above. For executable order-book sides: Bybit — Order Book.